Field
The present disclosure relates to network management. More specifically, the present disclosure relates to a method and system for providing adaptive link aggregations (LAGs) and virtual link aggregations (VLAGs).
Related Art
The exponential growth of the Internet has made it a popular delivery medium for multimedia applications, such as video on demand and television. Such applications have brought with them an increasing demand for bandwidth. As a result, equipment vendors race to build larger and faster switches with versatile capabilities, such as multicasting, to move more traffic efficiently. However, the size of a switch cannot grow infinitely. It is limited by physical space, power consumption, and design complexity, to name a few factors. Furthermore, switches with higher capability are usually more complex and expensive. More importantly, because an overly large and complex system often does not provide economy of scale, simply increasing the size and capability of a switch may prove economically unviable due to the increased per-port cost.
As more time-critical applications are being implemented in data communication networks, high-availability operation is becoming progressively more important as a value proposition for network architects. It is often desirable to aggregate multiple links to a switch (referred to as a link aggregation), or links to multiple switches (referred to as a virtual link aggregation or a multi-chassis trunk) to operate as a single logical link to facilitate load balancing among the multiple links/switches while providing redundancy. This ensures that a link failure, or a device failure for the case of a virtual link aggregation, would not affect the data flow. A switch participating in a virtual link aggregation can be referred to as a partner switch of the virtual link aggregation.
Currently, such link aggregations or virtual link aggregations in a network have not been able to provide efficient adaptive forwarding for different traffic flows. A traffic flow is often identified based on a source address, a destination address, and/or corresponding ports. If the packets of different traffic flows are forwarded via only a few specific links of the (virtual) link aggregation, while the other links remain underutilized, the (virtual) link aggregation may not be able to redistribute the packets to use the underutilized links. As a result, the packets become bottlenecked at those specific links and fail to utilize the bandwidth offered by the other links of the (virtual) link aggregation.
While link aggregation and virtual link aggregation bring many desirable features to networks, some issues remain unsolved in efficient adaptive forwarding.